Programmed cell death 1 ligand 1 (PD-L1)

"PD-L1 long peptide antigens" refers to synthetic peptides derived from sequences of PD-L1 (Programmed cell death 1 ligand 1, also CD274 or B7-H1), a type I transmembrane glycoprotein in the immunoglobulin superfamily. PD-L1 is not itself a peptide antigen but a receptor that binds PD-1 on T cells to suppress immune responses, particularly in cancer. These peptides (e.g., L1-L15 from PD-L1 regions like 19-26, 52-79, 111-127) mimic PD-L1 fragments to bind PD-L1 or PD-1, blocking their interaction for immunotherapy. PD-L1 has an extracellular IgV-like domain (with β-strands A-G and motifs like RMLDVEKC), transmembrane domain, and intracellular tail (with DTSSK, QFEET). It is a validated therapeutic target via antibodies that compete at the PD-1 binding site.[1][2][4][5][7][8][10]

Other names

CD274B7-H1PDCD1 ligand 1

Binding to PD-L1 extracellular IgV domain to block PD-1 interaction, steric hindrance of PD-1-PD-L1 interface, interference with PD-L1 β-sheet regions (e.g., GFCC' β-sheet, BC/FG loops)